Technical Field
The present disclosure relates to a seatback frame, and a resin for employing in a seatback frame, of an automobile.
Related Art
From the perspectives of ease of molding and weight reduction, resin-molded seatback frames are being adopted in vehicle seats of automobiles in recent years. Such seatback frames are formed in a substantially rectangular shape in front view, and include an upper side frame section extending along a seat width direction at an upper section of the seatback frame, and a pair of side frame sections extending along a seat up-down direction and connected to both seat width direction end portions of the upper side frame section (see, for example, Japanese Patent Application Laid-Open (JP-A) No. 2014-4977).
When such a seatback frame is applied to a vehicle seat, during a rear-end collision of the vehicle, for example, the head of an occupant collides with a headrest, such that load from the headrest is input to the resin-molded seatback frame, and load is transmitted from the upper side frame section, through the side frame sections, to a seat cushion frame. When this occurs, stress may concentrate at the connecting portions between the upper side frame section and the side frame sections.
Namely, in resin-molded seatback frames, it is desirable to suppress stress from concentrating at the connecting portions between the upper side frame section and the side frame sections when load is input from the headrest.